Die casting machine



Jan. 18, 1944. M, HELD 2,339,265

DIE QASTING MACHINE:

Filed Dec. 1, 1941 4 Sheets-Sheet l INVENTOR -i I MAX O.HELD

ATTORNEYS Jan. 18. 1944. M. o. HELD DIE CASTING MACHINE 4 Shets-Sheet 2 Filed Dec. 1, 1941 VlIIlII'lI'lIIlI/I J IIIIIIIIIIIIIIIII R mm) 0 x A i V: B JQ ATTORNEYS Jan. 18, 1944. Q H

DIE CASTING MACHINE Filed Dec. 1 1941 4 Sheets-Sheet 3 INVENTOR MAX O.HELD- ATTORNEYS Jan. 18, 1944. M. o. HELD DIE'CASTING MACHINE Filed Dec. 1, 1941 '4 Sheets-Sheet 4 INVENTOR MAX OHELD I ATTORNEYS Patented Jan. 18, 1944 UNITED STATES PATENT OFFICE DIE CASTING MACHINE Max 0. Held, Milwaukee, Wis.

Application December 1, 1941, Serial No. 421,148

Claims.

This invention appertains to die casting machines and is an improvement on my Patent No. 1,810,173, issued to me June 16, 1931.

One of they primary objects of my'invention is to generally improve the construction and operation of my machine whereby the same will function in a more accurate and reliable manner.

Another salient object of my invention is to provide novel means for detachably holding the cylinder for the molten metal in the melting pot and in correct position against the nozzle, said means permitting desired adjustment of the cylinder and ease of assembly.

Another important object of my invention is to provide means for supporting the dies and' porting means including a track onthe frame of the machine and rollers disposed at the outer endsroi the operating rods for the dies, with means whereby the track and rollers can be quickly adjusted relative to one another to suit varying temperatures and other operating conditions.

A further object of my invention is the provision of a novel arrangement of operating rods and Lbushings for the die plates, so as to insure theproper opening of the die plates and the tight accurate closing of the die plates.

A further important object of my invention is the provision of novel tension rollers for engaging the upper ends of the die plates upon the closing thereof for holding the die plates in proper position and tight against the inlet for the 'molten metal. g

A still further object of my invention is to provide novel means for operating the ide core pins during the operation of the-machine, so as to assure the proper withdrawal of the pins from the casting during the opening movement of the die plates, and the proper insertion of the pins during the closing of the die plates;

With these and other objects in view, the invention consists in the novel construction, arrangement and formation of parts, as Will be hereinafter more specifically described, claimed and illustrated in the accompanying drawings.

In the drawings:

Figure 1 is a side elevational view of my improved die casting machine.'

Figure 2 is a longitudinal sectional view through my machine.

Figure 3 is a fragmentary horizontal sectional view through my machine taken on the line 33 of Figure 1, looking in the direction of the arrows.

Figure 4 is a fragmentary sectional view taken on the line 44 of Figure 2 looking in the direction of the arrows and showing the melting pot and the novel means utilized for holding the cylinder for the molten metal in the correct desired position in said pot.

Figure 5 is an enlarged detailed fragmentary sectional view taken onthe line 5.5 of Figure 1 illustrating the roller and track for supporting the die plates and associated operating parts during the reciprocation of said die plates.

Figure 6 is an enlarged detailed horizontal sectional view taken on the line 6 6 of Figure 2. looking in the direction of the arrows showing the novel tension rollers employed for engaging the upper endsof the die plates.

Figure 7 is a sectional view taken at right an-' gles to Figure 6 and on theline 1-1 of Figure 6.

Figure 8 is an enlarged fragmentary detailed vertical sectional view taken on the line 88 of Figure 1 looking in the directionof the arrows and showing the means employed for actuating the side core pins.

Referring to the drawings in detail, wherein similar reference characters designate corresponding parts throughout the. several views, the letter Mv generally. indicates my improved die casting machine. As stated in the introductory paragraph, the machineM is of the same generalcharacter as that shown in my prior patent and hence the present machine will not be. described in all of its details. -1-Iowever, it is to be noted that the improved machine M includes a supporting frame [0 embodying spaced side and end walls and corner standards or legs ll. The frame also includes a transversely extending partition i2 which forms an end wall of a heating chamber i3 disposed within the frame. The

heating chamber I3 is provided with a suitable lining M of refractory material.

A melting pot I5 is supported in the heating "chamber to receive molten metal and is heated by mean of one or more. burners l6 of suitable provide a longitudinally extending trough I9 in the bottom of the pot.

An up-turned elbow haped nozzle 20 issecured to one end of themelting pot, preferably at some distance above the bottom wall of said pot. As illustrated, the nozzle is a separate member screwed on to the melting pot and its inner end can be beveled to form a seat, the purpose of which will be later set forth. If preferred, means can be provided for heating the nozzle to avoid the cooling of the molten metal therein.

Arranged within the melting pot I is a horizontally disposed cylinder 2|. The forward end of this cylinder is beveled to form an accurate fit against the bevel seat on the inner end of the nozzle 20. is closed by a cap 22, and the cap at this end of the cylinder rests upon a holding block 23 arranged in the bottom of the pot. V

In accordance with my present invention, I provide novel means for holding the cylinder on -said block and tight against the nozzle seat. This means includes a Y-shaped bracket 24 which extends into the pot. The lower end of the bracket has formed thereon a depending wedge shaped shoe 25 which is adapted to fit between one end wall of the pot and the cap 22 for the cylinder 2|. By referring to Figure 2, it will be noted that the outer face of the cap is inclined to agree with the shape of the wedge shoe. The upper ends of the bracket 24 are engaged by adjustable set screws 26 and these screws can be carried by plates 21 bolted or otherwise fastened to the pot. By adjusting screws 26 in one direction it can be seen that the bracketcan be urged downward between the cylinder and the adjacent end wall of the pot which will effectively urge the'cylinder forwardly against the nozzle. A set screw 28 can be carried by the shoe for engaging the rear-end of the cylinder so as to prevent the cylinder from riding up from the block 23.

By this arrangement of bracket and wedge shoe, ease of assembly is assured and the news-'- sity for boring the end wall of the pot for an adjusting screw as shown in my prior patent is disposed with.

A piston 29 is mounted for reciprocative movementin the' cylinder 2| for forcing molten metal from the cylinder into the nozzle. A slot like opening 30 is formed along the top of the cylinder to permit molten metal to enter into the cylinder. and one or more openings or ports 3| are formed inthebottom of the cylinder for the same purpose and also for permitting the cylinder and its communicating nozzle to be completely drained whenthe molten metal is removed from the meltingpot, To permit drainage-of the molten metal from the melting pot a valve 32 of the rotatable plug type is carried by the bottom of the pot. A receptacle 33 is'disposed below the meltingpot to receive metal drained from the pot.

The piston 29 in the cylinder 2| receives an upstanding pin 34 carried by a slide head 35. This slide head 35 is fastened to the forward end of a rack bar t6, which is slidably mounted in suitable guide bearings 3'l'carried by the frame of the machine. A transversely extending shaft 38 is journaled on the machine and is'provid'ed with a pinion 39 for meshing with the rack bar. A sprocket 40 is secured to one end of the shaft 38 and hastrained thereabout a sprocket chain 4|; 'One" end of the chain is secured to a rod 42 and the opposite end of the rod is pivotally mounted, "as at '43, to an operating hand lever 44. The lower end of the hand lever is in turn rock- The opposite end of the cylinder 2| ably mounted, as at 45, on a bracket 46 rigidly fastened to one of the corner legs or standards II of the machine. A plurality of idler sprocket wheels 41 are mounted on the side of the machine and the sprocket chain is trained over said idler wheels. These idler sprocket wheels are employed in order to insure the retention of the chain on the sprocket wheel 45. A tension spring 48 connects the end of the chain below the sprocket wheels to the frame of the machine or to the floor to create a continuous tension on the chain. Another sprocket wheel 49 is secured to the shaft 38 and has trained thereabout a sprocket chain 55. One flight of the chain passes over an idler sprocket wheel 5| and the other flight of the chain passes over a similar idler sprocket wheel 52. 5| and 52 are rotatably mounted on the frame of the machine. The flight of the chain 50 which passes over the wheel 52 carries a weight 53 at its lower end which acts to rotate the wheel 52 for moving the rack bar 36 and its connected piston 29 to their retracted positions. The other end of the chain 50 carries a small weight 54 which insures retention of the chain on the sprocket wheel 5|. The forward movement of the handle 44 by the operator serves to move the piston 29 in the cylinder 2| for urging molten metal under pressure into the nozzle 20, while the counter-weight 53 serves to move the piston and its connected handle to their retracted positions. A hollow tip 55 is secured to the upper end of the nozzle 20 and is provided with an upwardly converging conical opening 55. The upper end of the tip is rounded and fits within a correspondingly shaped socket in metal bushing 51, which is fixed in the bottom wall of a box-like die casing 58'. The die casing 58 is hinged to the ad- 'jacent end of the frame i0 by pivotal connections '59. so as to be capable of swinging away from the nozzle tip 55. Suitable clamps 60 serve to retain the die casing 58 in its operative position with the nozzle tip 55 fitting closely in the socket formed "in the bushing 51 carried by the die casing." The die casing 58 is preferably rectangular in cross section and is open at its sides and also along part of .its'top and bottom walls and at its outer end. Slidably fitted within the die casing for horizontal movement are a pair of die'shoes 6| and 62 which rest on the floor of the die casing and suitable guides are provided on the die casing for said shoes.

The die shoes 5| and 62 are reciprocated within the die casing, the former traveling a greater distance than the latter. Complementary die plates 63 and 64 are secured to the adjacent faces of the die shoes BI and 62, respectively, and are in face to face contact when the die shoes are at their inner positions and also during a portion of the travel of thedie' shoes as will be later described. When'the abutting die plates are at their inner positions, the cooperating die cavities thereof are in position to communicate with an opening or port 65 formed in the bushing 51, the upper face of this bushing being flush with the floor of the die casing. In many instances the die cavities can be arranged for the simultaneous formation of a plurality of castings connected to the same sprue, from which the castings are later separated. The lower edge of the die plate 64 is preferably provided. with means for cutting the ingate or sprue during the outward movement of the die plates and shoes. The die plates can have means for cooling the same to a desired These idler sprocket wheels .rods 66.

adapted to bear against the upper edges of the temperature for insuringthe rapid solidification of the metal in the die cavities. w

The means for operating the die plates and their shoes includes two pairs of spaced parallel These rods slidably extend through the die shoe 62 adjacent its opposite ends and the forward ends of these rods are reduced in diameter to form shoulders 61 which engage against the inner face of the die shoe 6|. The reduced portions 68 of the rods 66 extend through the die shoe BI and nuts 69 are threaded on the outer ends of the reduced portions of the rods to firmly clamp the die shoe 6| on said rods. Slidably mounted on the rods 66 are operating sleeve or tubular bushings 10. These bushings l8 slidably extend through the front wall of the die box or casing 58 and engage the outer face of the die shoe 62. The arrangement of the rods 66, the bushing 18 and associate parts form an impor- .tant feature of my present invention. The rods 66 are all firmly connected at their rear ends by a frame II and slidably mounted on the rods 66 is an operating frame 12 for the bushings or sleeves l6 and this sliding frame 12 engages the bushings. The rods 66 have an intermediate frame 13 rigidly secured thereto between the sliding frame 12 and the outer frame ll. Toggle links 14 and 15 have their outer ends pivotally connected as at 16 and 11 to the frames 12 and 13, respectively. The toggle links are'connected at their adjacent ends by a pivot 18 to permit their upward movement. However, the adjacent ends of the toggle links I4 and 15 are provided with stop abutments which prevent the downward movement of the toggle links beyond a position in which these links are alined with each other, see Figures 1 and 2. In this position of the links, the axis of the pivots l6, l1 and 18 lie substantially in the same plane. With the toggle links 14 and 15 so alined, the. frames 12 and 13 are separated which causes the bushings or sleeves 78 to press the die shoe 62 toward the die shoe 6| while the rods 66 draw the die shoe 6| toward the die shoe 62. The portions of the toggle links 14 adjacent the pivot 16 are provided with downwardly inclined cam tongues 19, and these tongues have a cam engagement with the end wall of the die casing 58 to break the toggle joints formed by the toggle links 14 and 15 as also will be more clearly set forth, for permitting the die plates and shoes to separate. The rear frame H carries a shaft 89 on which is mounted for oscillatory movement a tubular shaft 8|. This tubular shaft 8| has firmly connected thereto upwardly extending operating rods or levers 82. Clamp members 83 are secured tointermediate portions of the levers 82 and are pivotally connected by links 84 to stationary extension arms 85 having an adjustable connection with supporting arms 86 secured to the upper portion of the die casing 58. To prevent relative displacement of the arms 85 and 86, their abutting faces may be toothed or corrugated.

Clamp members 8'! are adjustably secured to the upper portions of the levers 82 and have pivotal connections with the end portions of a pair of bent links 88. The bent end portions of the links 88 are pivotally connected to crank arms 89 carried on a shaft 99 journaled in bearings 9| on the die casing. An extended end of the shaft 90 has secured thereto an operating wheel 92 and this wheel has adjustably mounted thereon the die operating lever 93. The levers 82 also have secured thereto brackets 94 and thesebrackets carry depending adjustable. rods 95, which are toggle links 14 when the die plates are in their abutting position. This relation serves to hold the toggle joints closed and thereby insures against separation of the die shoes when the molten metal is forced between the die plates under pressure.

When the die operating lever 93 is swung forwardly from the position shown in Figures 1 and 2, the upstanding rock levers 82 are moved rearwardly, These rock levers have floating pivotal connection on the links 84 and consequently the lower ends of the rock levers 82 move forwardly toward the dies and function to force the pairs of rods 66 forwardly. As the slide frame 12 is locked on the rods 66 against the bushings or sleeves 18 by the toggle links the initial movement of the rods is such to carry the die shoes6| and 66 together until the cam tongues 19 on the toggle links strike the die casing 58. As the die shoes move in unison the die plate 64 moves over and closes the opening in the bushing 51. During the rocking of the levers 82 the rods 95 are moved away from the toggle and consequently when the toggle links 14 strike the die casing .the toggles will be broken and upon continued forward movement of the rods 66 the die shoe 6| with its die plate 63 will move away from the die shoe 62 and its plate 64.

On the return movement of the die operating lever 93 by the operator, the die shoe 6| moves inwardly until thedie plates 63 and 64 engage, whereupon the die shoe 62 moves with, the die shoe 6| t0 the innermost position shown in Figure 1. The approach movement of the die shoes 6| and, .62 also serves to lengthen the toggles, and thecompletealinement of the toggle links is insured by the engagement of the rods 95, with the upper edges of the toggle links 15.

. .casting on the die plate 63 when the die plates separate.

Another feature of my present invention resides in the means for forming a rolling support for the die operating rods 66 and the parts coupled therewith. In my previously patented machine considerable binding tookplace due to expansion from heat and other operating conditions. In order to facilitate movement of the rods and the dies the ends of the shaft 88 have rotatably mounted thereon suporting rollers 96. These rollers 96 have rolling contact with tracks 91 mounted on the frame l9 of. the machine. The tracks are adjustably supported in a novel manner whereby the tracks can be raised and lowered relative to the rollers to suit varying operating conditions. As illustrated, the tracks 91. carry spaced depending brackets 98 which extend be.- tween the frame of the machine and a guide strap 99 which is securely bolted to the sides of the frame of the machine. The brackets 98 above and below the strap 98 have formed thereon outwardly extending ears I00 and these ears carry adjustable set screws |0| for engaging the upper and lower edges of the strap. By adjusting these screws the brackets and their tracks can be raised and lowered. If desired, the straps 99 can be provided with slots I02, through which extend bolts )3 carried by the brackets 98. The ends of these bolts have threaded thereon tightening nuts J64. for engaging the straps 99 to look. the

brackets 08 on the straps. Consequently, during "the sliding movement of the rods and dies 'the rollers 96 efiectively provides. rolling engagement its complete opened position, ejector pins I05 slidably extend into the die plate 63. These ejector pins I05 are rigidly secured to a slide plate 'I 06. The slide plate is mounted upon guide bolts I01 carried by thedie plate 63. A stop plate I08 is secured to the bolts and acts as a guide for a shank I09 which is securely fastened to slide plate I06. A head or nut H is fastened to the end of the shank I09 and has bearing againstsame an expansion Spring III which is coiledabout the shank. The inner end of the spring bears against the stop plate I03 which is fastened to the guide-bolts I01. Consequently the stop plate and the ejector pins I are normally held outwardly and in their non-ejecting position.

When the shoe is in its open position the end of the shank I09 is adapted to strike a set screw I-I-2 'fastened to a frame bar II3 of the machine. This screw I I2 can be adjusted so that the ejector pins will have the desired correct movements to force the casting from the plate 63.

A further important object of my invention is the provision of a means for creating a desired pressure on the upper ends of the shoes and die plates, so that the die plates will have the proper engagement with the bushing 51 through which the molten metal flows. rollers II4 which have rolling contact with the upper edges of the die plates. These rollers are carried by the lower ends of yokes -II5 which slidably extend through a guide flange I I6 formed on a supporting. bracket 1. This bracket is firmly fastened to the die casing 58. Each of the yokes II5 have secured thereto shanks II8 which slidably extend through a guide flange I I9 formed on the upper end of the bracket II'I.

Expansion springs I are coiled. about the shanks I I8 and the opposite ends of these springs engage the guide flange H9 and the upper ends of the yokes II5. Consequently, the springs I20 serve to normally urge the rollers downward. Movement of the shanks II8 are limited by nuts I2I threaded on the upper ends of the shanks. If desired, the upper edge of the die plate 64 can be slightly beveled to facilitate the rolling engagement of the rollers I I4 with the die plates incident to the movement of said plates. By referring to Figures 6 and 7 it can be seen that one of the .rollers are arranged in advance of the other two rollers and theserollers also function to steady the die plates during their opening and closing movement.

As in my patent machine, in order to permit the production of relatively complicated castings without interfering with the rapid operation of the machine, a core arrangement is provided which will permit the formation of openings or recesses in various parts of the castings. Core pins can be carried by the die plate 34 and these pins can form openings in the faces of the castings. In order to form openings in the ends of the castings, the die shoe 6| can carry bearing sleeves I22 for core plungers I23- These core plungers are adapted to extend into the die plates and the inner ends thereof carry the core pins. This also is shown inmy. prior .patent, but I'have provided an improved .means.;.ior insuring-the This means includes with the frame of the machine, which eliminates 'proper operation of the pins during the movement of the die plates and'shoes. In accordance with my invention,"the outer ends of the core -plun'gers I23 carry yokes I24 and the outer ends of these yokes carry anti-friction rollers I25. 'Also' extending through the yokes on the inner sidesof the rollers I25 are slide plates I26 and these slide plates have formed on their inner edges cam'surfaces I2'i. Guide rollers I28 are carried by the ends of the die shoe BI and these rollers I28 engage the inner edges of the slide plates I26. The outer ends of the slide plates I26 are pivotally connected, as at I29 to links I30. The inner ends of the links are in turn pivotally connected as as I3I to the frame of the machine. The outer ends of the links have connected thereto tension springs I32 and these springs are also fastened to guide brackets I33 which extend outwardly from the opposite sides of the die casing 58. The inner ends of the'slide plates I26 are connected by means of pivot pins I34 with links I35. The links. I35 are rockably mounted on brackets I36 by means of pivot pins I31. The brackets I35 are also securely fastened to the die casing 53. Adjustably carried by the outwardly extending brackets I33 are strike plates I38 and the rollers I25 are adapted to engage said strike plates when the dies are in their closed position.

Upon the initial movement of the die shoes SI and 62 toward the left (see Figure 3), the rollers I25 will roll off the strike plates I38 and upon the engagement of the rollers I28 with the cam surfaces I27, the plates I23 will be rocked and these plates will push out on the rollers I25 to move the core'pins carried by the plungers I23 from out of the casting.-

Upon the return movement of the shoes the rollers I28 will ride off the cam surfaces I21 and the springs I32 will tend to return the plates to their normal positions and upon the riding of the plunger rollers I25 upon the strike plates I38 the plungers with their core pins wil1 be moved inwardly.

The operation of the machine is the same as my machine referred to in my patent and consequently the operationof my present machine will be well understood by referring to said patent and to the foregoing description.

Changes in detail may be made without departing from the spirit or scope of this invention, but What I claim as new is:

1. In a casting machine, the combination-of a die casing having an opening through which molten metal is forced, a pair of die members slidably mounted insaid die casing and forming a mold cavity between them registerable with said opening, slide rods rigidly connected with one of said die members and movably passing through the other of said die members, guide sleeves loosely mounted upon said rods and slidable through the casing and engaging the outer face of said last mentioned die member, a frame member slidable on said rods for engaging the sleeves, a frame member. rigidly secured to said rods, toggle jointmeans connecting said frame members together for holding said die members together when said toggle joint means are straightened, opera-ting means connected with said rods for moving said die members, and means for automatically breaking said toggle joint means after a pre-determined travel of said die members fornpermitting said die members to separate.

2. In a casting machine, a supporting frame, aidie casting :rigidly. connected with said frame die member, a frame slidably mounted on the rods engaging the outer ends of the sleeves, a frame rigidly secured to said rods, toggle joint means connecting said frame members together for holding said dies together when said toggle joint means are in their extended positions, operating means connected with said rods for moving said die members, means for automatically breaking said toggle joint means after a predetermined travel of said die members for permitting said die members to separate and roller and track means between said rods and the frame of the machine.

3. In a casting machine, a supporting frame, a die casing rigidly connected with said frame having an opening through which molten metal may be forced, a pair of die members slidably mounted in said die casing and forming a mold cavity between them registerable with said opening, rods connected with one of said die members and movably passing through the other of said die members and casing, sleeves slidably mounted on said rods and in said casing having their forward ends engaging the last mentioned die member, a frame slidably mounted on the rods engaging the outer ends of the sleeves, a frame rigidly secured to said rods, toggle joint means connecting said frame members together for holding said dies together when said toggle joint means are in their extended positions, operating means connected with said rods for moving said die members, means for automatically breaking said toggle joint means after a predetermined travel of said die members for permitting said die members to separate, and a roller and track means between said rods and the frame of the machine, said rollers and tracks being adjustable relative to one another.

4. In a casting machine, a supporting frame, a die casing rigidly connected with said frame having an opening through which molten metal may be forced, a pair of die members slidably mounted in said die casing and forming a mold cavity between them registerable with said opening, rods connected with one of said die members and movably passing through the other of said die members and casing, sleeves slidably mounted on said rods and in said casing having their forward ends engaging the last mentioned die member, a frame slidably mounted on the rods engaging the outer ends of the sleeves, a frame rigidly secured to said rods, toggle joint means connecting said frame members together for holding said dies together when said toggle joint means are in their extended positions, operating means connected with said rods for moving said die members, means for automatically breaking said toggle joint means after a predetermined travel of said die members for permitting said die members to separate, and a roller and track means between said rods and the frame of the machine, said tracks being adjustable on said frame toward and away from the rollers.

5. In a casting machine, a supporting frame, a die casing carried by said supporting frame having an'opening through which molten metal may Lil be forced, a pair of die member's slidably mounted in said die casing and formin a mold cavity between them registerable with said opening, means for operating said diemembers including rods connected with one of said die members, a supporting shaft carried by the outer ends of the rods, operating levers rockably mounted upon the shaft, a pivotal floating connection between said levers intermediate their ends and said casing, means for operating the levers from the upper ends thereof, adjustable guide tracks carried by the supporting frame, and rollers on said shaft engaging said track;

6. In 'a' die casting machine, a die casing having 'anopeningthrough which molten metal may be forced, a pair of die members slidably mounted in said die casing and forming a mold cavity between them registerable with said opening when the die members are in one position, means for sliding said die members back and forth in said casing, and tension means engaging the upper ends of said die members for holding said die members in intimate contact with the bottom wall of said die casing.

'7. In a die casting machine, a die casing having an opening through which molten metal may be forced, a pair of die members slidably mounted in said die casing and forming a mold cavity between them registerable with said opening when the die members are in one position, means for sliding said die members back and forth in said casing, tension means engaging the upper ends of said die members for holding said die members in intimate contact with the bottom wall of said casing, said tension means including a bracket supported by the upper portion of the casing, downwardly spring urged yokes supported by the bracket, and rollers in said yokes for engaging the die members.

8. In a die casting machine, a die casing having an opening through which molten metal may be forced, a pair of die members slidably mounted in said die casing and forming a mold cavity between them registerable with said opening when the die members are in one position, means for sliding said die members back and forth in said casing, a tension means engaging the upper ends of said die members for holding said die members in intimate contact with the bottom wall of said casing, said tension means including a bracket supported by the upper portion of the casing, downwardly spring urged yokes supported by the bracket, and rollers in said yokes for engaging the die members, the upper faces of one of said die members being inclined for engagement with the rollers.

9. In a die casting machine, a supporting frame, a die casing connected with said frame having an opening through which molten metal may be forced, a pair of die members slidably mounted in said casing and forming a mold cavity between them registerable with said opening, means for moving said die members out of register with said opening and for effecting the separation of said die members, core means slidably mounted in one of said die members to enter said die cavity and being relatively movable out of said die cavity upon movement of said die member out of register with the opening in the die casing, means a for operating said core means including outwardly projecting brackets carried by the sides of the die casing, strike plates carried by the ends of the brackets, outwardly projecting yokes secured to said core means having rollers for engaging the strik plates when the die members are closed,

slide plates having cam surfaces extending through the yokes and engaging said rollers,

means rockably supporting the ends of the slide plates, and outwardly projecting rollers carried by one of said die members for engaging the cam surfaces of said slide plates.

10. In a, die casting machine, a supporting frame, a die casing connected with said frame having an opening through which molten metal may be forced, va pair of die members slidably mounted in said casing and forming a mold cavity between them registerabl with said opening, means for moving said die members out of register with said opening and for effecting the separation of said die members, core means slidably mounted in one of said die members to enter said die cavity and being relatively movable out of said die cavity upon movement of said die member out of register with the opening in the die casing, means for operating said core means including outwardly projecting brackets carried by the sides of the die casing, strike plates carried by 

